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Z-Flex 3" Diameter 1-Ply Aluminum Flex Duct, 1.5 10 15 20+' Lengths

by Z-Flex
Original price $14.95 - Original price $109.50
Original price
$14.95 - $109.50
Current price $14.95


Made in America3" diameter flexible aluminum duct in your choice of various lengths

Semi rigid, lightweight, non-insulated, 1 ply aluminum duct. The part number for our popular 19' length is 1TLXXXX0319.

This duct is commonly used for Takagi tankless water heaters to connect the 3" fresh air inlet on the Takagi tankless heater to the 3" inlet on the fresh air hood or concentric vent kit.

→ This duct can be trimmed to with metal scissors or a hacksaw to your desired length.
→ To fasten this 3" aluminum duct to other parts, order the 7HS44XX 3" gear clamps shown in the blue Related Gadgets tab above.

Use for fresh air intake only. Do not use as a chimney liner. For that, use flexible stainless steel gas liner.

We also have this duct in 2", 3", 4", 5" and 6" diameters and various lengths up to 50 feet. Please search or contact us for price and availability.


Material: Aluminum
Maximum Rated Velocity: 20.3 m/s (4000 fpm)
Maximum Positive Pressure: 3kPa (12 in. WC)
Maximum Negative Pressure: 0.25 kPa (1 in. WC)
Temperature Range: -40°F to +600°F ( -40°C to +316°C )
Bend Radius: 1.5 x diameter
Available Sizes: 2” to 24”
Standard Lengths" 10 feet
ULC Listing: Class 1 Connector
Warranty: Limited Lifetime

The Triple Lock T/L system by Flexmaster is a lightweight, semi-rigid, non-insulated air duct. It's made using a dead soft aluminum strip which is spirally wound and mechanically joined together. This forms an air-tight and leakproof three-ply mechanical seam. It is self-supporting and corrosive resistant. With its ULC-S110 and UL-181 Class 1 rating, it provides excellent strength and flexibility. It is adaptable to any heating, ventilation and air conditioning system, even with high-pressure.